powerpc/mm: Define radix_enabled() in one place & use static inline

Currently we have radix_enabled() three times, twice in asm/book3s/64/mmu.h
and then a fallback in asm/mmu.h.

Consolidate them in asm/mmu.h. While we're at it convert them to be
static inlines, and change the fallback case to returning a bool, like
mmu_has_feature().
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/include/asm/book3s/64/mmu.h

@@ -23,13 +23,6 @@ struct mmu_psize_def {
 };
 extern struct mmu_psize_def mmu_psize_defs[MMU_PAGE_COUNT];
 
-#ifdef CONFIG_PPC_RADIX_MMU
-#define radix_enabled() mmu_has_feature(MMU_FTR_TYPE_RADIX)
-#else
-#define radix_enabled() (0)
-#endif
-
-
 #endif /* __ASSEMBLY__ */
 
 /* 64-bit classic hash table MMU */

arch/powerpc/include/asm/mmu.h

@@ -163,6 +163,18 @@ static inline void assert_pte_locked(struct mm_struct *mm, unsigned long addr)
 }
 #endif /* !CONFIG_DEBUG_VM */
 
+#ifdef CONFIG_PPC_RADIX_MMU
+static inline bool radix_enabled(void)
+{
+	return mmu_has_feature(MMU_FTR_TYPE_RADIX);
+}
+#else
+static inline bool radix_enabled(void)
+{
+	return false;
+}
+#endif
+
 #endif /* !__ASSEMBLY__ */
 
 /* The kernel use the constants below to index in the page sizes array.
@@ -230,9 +242,5 @@ static inline void mmu_early_init_devtree(void) { }
 #  include <asm/mmu-8xx.h>
 #endif
 
-#ifndef radix_enabled
-#define radix_enabled() (0)
-#endif
-
 #endif /* __KERNEL__ */
 #endif /* _ASM_POWERPC_MMU_H_ */